The Republican numbers among 18-29 year olds are awful.
Republicans have little to offer the young-adult vote. This age group gives President Obama 58% approval, which is decidedly above the approval rates for other, older voters. This age group might be more minority than other generations, but not that much more. I see no reason to believe that Virginia is significantly more D than the rest of America. Virginia is close to being the likely tipping-point state in 2016, and in view of the state straddling regions of America (Northeast urban America, Appalachia, and the Old South) it is a fairly-good microcosm of America; Florida and Ohio are the others.
Should the young-adult vote vote as it did in 2008 and in large numbers nationwide, then the GOP is in big trouble nationwide. There is no new source of right-wing voters. Although Virginia has no Senate seats in play, we can readily see trouble for Republicans holding onto the Senate... and quite a few House seats. If Republicans lose lots of even to R+5 seats they then lose the House.